just to answer myself ... that's just for all who help
the plug-in versdion is simply not compatible with the latest version of mach3....
I' have downgraded to v 2.58 .. and the plug in that is included in the install package work like a charm ...
so if it could be helpfull for other, who like me, lost so many time to search and test ....
it's really strange that the plug in available to download has not been tested with 3.xx version ...